Since the commercial introduction of the plastic film grocery bag in this country, its acceptance has steadily grown because of its many advantages over kraft paper grocery bags. The many advantages connected with present-day plastic grocery bags include their ability to be unaffected by water, the fact that they are not as bulky as paper grocery bags, are less expensive and stronger than paper bags, as well as the fact that most have carrying handles, making them easier to use.
However, because of the inherent lack of rigidity of the plastic film employed in the manufacturing of these bags, special means are required for suspending packs of plastic bags and for holding the foremost bag in a pack in a position conducive to filling the bag. As may be readily appreciated, long lines at the checkout counter of a supermarket are annoying to the customers and baggers. If a bagger utilizing plastic bags has to fumble to open each bag, productivity suffers.
In certain bag dispensing systems wherein the bag pack is used in conjunction with a suspension and dispensing means, the use of plastic bags will outperform paper grocery bags from an ease-of-handling and time standpoint. There is, however, always room for improvement, and any innovation which will cut down handling time and/or in any way facilitate the use of such bags amounts to a significant advance in the art.
Disclosures which relate to improvements in plastic grocery bags and dispensing systems include U.S. Pat. No. 4,165,832 to Kuklies et al., which describes packs of thermoplastic grocery sacks wherein the individual bags are designed to be held in registration by being thermally welded together at a suspension tab member which extends from the center region of the bag mouth. While this type of unitization is effective in maintaining the sacks in secure uniform registration at the bag mouth region, they do not keep the handles in registration. Such a bag pack is structured to be suspended from the center of the pack and it is awkward during dispensing and bag filling to deal with the loose unsecured handles particularly in bag packs containing over 100 bags in the pack.
U.S. Pat. No. 4,676,378, issued to Baxley et al., discloses a technique for suspending a pack of bags from the handles of the bags in the bag pack. The suspension points are located intermediate the top and the bottom of the handles. This is accomplished by threading each stack of handles onto anchored spaced parallel suspension rods through a suspension orifice in each handle. This means or manner of suspension permits individual bags to be opened with one swipe of the hand, leaving the bag in its opened condition, i.e., front panel separated from the back panel, with the handle loops spread open and suspended from the suspension rods. This broad means will be the suspension means involved in the instant invention.
The Baxley et al. patent also discloses a technique for automatically opening the next bag in a suspended bag pack as a loaded bag is removed from the system. This is essentially the same technique as is disclosed in U.S. Pat. No. 4,106,734, issued to Walitalo, which teaches suspending handle-less bags from suspension rods and utilizing an adhesive area just below the bag mouth on the front of each bag in the pack. This arrangement causes the next adjacent bag in the pack to be in separable adhesive contact with the bag that precedes it. Thus, after a bag is loaded and during removal of the loaded bag from the rack, the front panel of the following bag will tend to follow along a short distance before release. This action causes each following bag to more or less automatically open as a filled bag is removed.
U.S. Pat. No. 4,796,759, issued to Schisler, is directed to a pack of thermoplastic film handled grocery sacks. A hole is present in each handle so as to receive a rod therethrough designed to support the bag pack by the handles. A center support tab extends from the mouth of each bag and the tabs are joined together by welding or gluing to secure the bags in a pack. A line of perforations separate the support tab from the bag mouth. Below the perforation line of each bag is a "glued or welded localized zones 9" which ensures connection between the rear wall of one bag and the front wall of the next bag and so on through the bag pack. Above this point 9, the welded-together support tabs maintain the bags in registration and the localized glued or welded zones 9 assists in opening the bags during the dispensing and loading of the same. This construction also has the disadvantage that no provision is made for maintaining the handles in registration.
While these techniques of enhancing the system of suspending, dispensing and filling grocery sacks have merit, those involving adhesives have the disadvantage of leaving each bag with a more or less localized tacky region on the outside surface of each bag. As may be appreciated, the use of adhesives introduce an additional messy step into the manufacturing process.
U.S. Pat. No. 5,335,788 to Beasley discloses self-opening polyethylene film bag stacks which do not utilize a separate adhesive layer between bags in the stack. At least an upper portion of the outer surface of the front and rear walls of each of the bags in the bag stack are corona treated. At least one compressed area extends transversely through the bag stack in the upper portion of the bags such that the stack has a decreased thickness in the localized area and so that adjacent outer wall corona treated surfaces defined by the localized compressed area are releasably adhered together.
Other advances include U.S. Pat. No. 4,811,417, issued to Prince et al., which shows a bag pack having vertical slit support handles therein, wherein the handles are melt-bonded together at the top by means of a heated pin device.
In U.S. Pat. No. 4,989,732, which is incorporated herein by reference in its entirety for all that it discloses, there is described a system for suspending and dispensing grocery sacks. The bag packs are suspended through orifices in the handles by a pair of spaced parallel cantilevered rods. Dispensing of the bags in a manner which will cause the next following bag to be partially opened upon removal of a lead bag is facilitated by the provision of pressure bonded areas in the handles and in the region of the bag mouth. As a lead bag is removed the next adjacent bag tends to follow along for a short distance during which the front panel of the bag separates from its rear panel. When the lead bag finally releases from the following bag, the next bag is in a partially opened condition so that the supermarket bagger can easily access the interior of the bag.
Application Ser. No. 07/529,806, filed on May 29, 1990, which is a continuation-in-part of application Ser. No. 07/495,070, filed on Mar. 19, 1990, the contents of which are incorporated herein by reference, discloses a thermoplastic film bag pack comprising a plurality of the bags stacked in at least general registration in a layflat condition, each of the bags comprising a bottom, side walls and an open mouth top portion, the open mouth portion comprising handles located at opposite end regions thereof, at least a portion of the external surface of the film of the open mouth and handles region having been subjected to a corona discharge treatment to such an extent that the pressure and cutting action forming the bag mouth and handles will cause adjacently facing corona discharge treated cut-edge regions to releasably adhere together until a moderate force separates them.
Despite these advances in the art, it would be a significant advance if further handling time reductions or improvements which, in any way, facilitate the use of such bags could be accomplished.